The present invention relates to reversible axle spindles and, more particularly, to a reversible axle spindle sized to accommodate different wheel hub bearing surface dimensions for use in an axle assembly on small sailboat and dinghy boat dollies.
Boat dollies are lightweight devices used to portage small sailboats or dinghies to and from water, to hand launch small sailboats or dinghies into water from beaches, ramps or other shores and to store these small boats in boatyards. A boat dolly is generally smaller than a boat trailer with smaller wheels and is not suitable for towing a boat on the road. A number of dolly designs are currently available in the marketplace consisting of a lightweight longitudinal frame, transverse handle, axle that extends transverse to the longitudinal frame with spindle and wheels.
Most dollies and their corresponding axles are framed with square aluminum tubing, but may be of other configurations. (Examples shown in FIGS. 1A and 1C). Wheels are usually attached to the axle with a spindle (26) that extends longitudinally from the axle frame. Various brackets (23 & 23A) and fasteners (21) are used to attach the spindle to the axle frame (22) as shown in FIGS. 1A through 1C. The spindle inserts through a hub of the wheel and the wheel is secured on the spindle by means of a cotter pin or similar attaching device on its outer end. On commercially available small sailboat dollies, the original equipment spindle is often sized to accept wheels with hubs sized approximately one inch in diameter and a hub width of approximately three inches to five inches. The spindle will not accept wheel hubs with different dimensions; thereby limiting the use of more readily available aftermarket replacement wheels.
The wheels and tires are usually of low load specification, since small boat dollies are subjected to low load forces (typically less than 500 pounds). They have a limited life span due to deterioration of the rubber tire and/or the plastic wheel rim resulting from dolly use in corrosive environments such as fresh or salt water, outside storage and UV radiation from the sun. Consequently, wheels are considered replaceable items. For replacement, wheels and tires are typically sold as a unit. Options for these replacement wheels are limited, since more readily available aftermarket wheel and tire units meeting tire load specifications of the original equipment have hubs requiring axle spindles with a smaller diameter size than the original equipment spindle.
Specialty wheels that offer desirable characteristics useful for portage of boats over different terrains and ramp launching conditions are also available aftermarket. These include wheels of different widths and/or diameters designed for sandy beaches or rough terrain and wheels with tires that will not go flat. However, these aftermarket wheels cannot be used with the original equipment spindle because they have either wheels hubs that are smaller in diameter than the original equipment spindle or wheel hubs that require a longer spindle. Use of these aftermarket wheels requires the end user to also purchase an aftermarket spindle. No size adapter systems are commercially available.
Accordingly, an object of the present invention is to provide a reversible axle spindle that will accommodate both original equipment manufacturers wheels and specialty wheels with different sized wheel hub bearing surfaces.
Another object is to provide a reversible spindle that offers the end user greater flexibility and economy in the purchase of replacement and original equipment manufacturer aftermarket wheels.